Zonal Mean Winds Induced by Solar Diurnal Tides in the Lower Thermosphere for a Solstice Condition

1984 ◽  
pp. 181-197 ◽  
Author(s):  
Saburo Miyahara
Keyword(s):  
Lower Thermosphere ◽  
Diurnal Tides

scholarly journals Global distributions of diurnal and semi-diurnal tides: observations from HRDI-UARS of the MLT region

2002 ◽  
Vol 20 (11) ◽  
pp. 1877-1890 ◽  
Author(s):  
A. H. Manson ◽  
Y. Luo ◽  
C. Meek
Keyword(s):  
Seasonal Changes ◽  
Middle Atmosphere ◽  
Lower Thermosphere ◽  
Wave Model ◽  
Global Scale ◽  
Radio Science ◽  
Contour Maps ◽  
June July ◽  
Longitudinal Variability ◽  
Diurnal Tides

Abstract. HRDI (High Resolution Doppler Interferometer-UARS) winds data have been analyzed in 4° latitude by 10° longitude cells at 96 km to obtain global contour maps of solar-tidal amplitudes and phases, and also mean winds. The solstices June–July (1993), December–January (1993–1994), and one equinox September–October (1994) are shown.  The 24-h diurnal tide that maximizes near the 20–25° latitude has significant seasonal changes with equinoctial maxima, and very clear longitudinal variability. Maxima are very clear over the oceans. In contrast, the 12-h semi-diurnal tides that maximize near the 40–55° latitude have very strong seasonal changes with winter maxima, and more modest longitudinal changes. The similarities with MLT (mesosphere-lower thermosphere) radar observations (90 km) and the GSWM (Global Scale Wave Model) are very satisfactory. The mean winds are consistent with expectations and show clear poleward flow from summer to winter hemispheres in the solstices.Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides) Radio science (remote sensing)

Planetary wave-tide nonlinear interactions increase the variety of MLT waves in summer 2019

2021 ◽  
Author(s):  
Maosheng He ◽  
Jorge L. Chau ◽  
Jeffrey M. Forbes ◽  
Denise Thorsen ◽  
Guozhu Li ◽  
...  
Keyword(s):  
Planetary Wave ◽  
Lower Thermosphere ◽  
Planetary Waves ◽  
Diurnal Tide ◽  
Nonlinear Interactions ◽  
Zonal Wavenumber ◽  
Spectral Peaks ◽  
Northern Hemispheric ◽  
Mesosphere And Lower Thermosphere ◽  
Diurnal Tides

<p>Mesospheric winds collected by multiple meteor radars at mid-latitudes in the northern hemispheric are combined to investigate wave activities in June—October 2019. Dual-station approaches are developed and implemented to diagnose zonal wavenumber $m$ of spectral peaks.  In  September—October, diagnosed are quasi‐10‐ and 6‐day planetary waves (Q10DW and Q6DW, $m=$1), solar semi-diurnal tides with $m=$1, 2, 3 (SW1, SW2, and SW3), lunar semi-diurnal tide, and the upper and lower sidebands (USB and LSB, $m=$ 1 and 3) of Q10DW‐SW2 nonlinear interactions.  During June— September, diagnosed are Rossby-gravity modes ($m=$3 and 4 at periods $T=$ 2.1d and 1.7d), and their USBs and LSBs generated from interactions with diurnal, semi-diurnal, ter-diurnal, and quatra-diurnal migrating tides. These results demonstrate that the planetary wave-tide nonlinear interactions significantly increase the variety of waves in the mesosphere and lower thermosphere region (MLT).</p>

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